 Click to Chat

1800-1023-196

+91-120-4616500

CART 0

• 0

MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
`        If the sum of n terms of an A.P is n2 then its common difference is ______`
4 years ago Vijay Mukati
2590 Points
```							common difference, d = 2(n-a)/(n-1)
```
4 years ago
```							Ans is 2 bcz AP is 1,3,5,7,9,11 here u can see that sum of first 2 terms is 4 thatis 2 sq. , sum of first 3 tems is 9 that is 3 sq. And so on
```
2 years ago
```							n/2 [ 2a +(n-1)d] = nOn solving ,2n - 2a = (n-1)d=> d = 2(n-a)/(n-1)Now, when n=1,d = 2(2-a)/(2-1)      = 4 - 2aWhen n=2,d= 2(3-a)/(3-1)    = 3-aWe know, that d is constant in an AP series. Hence, d = 4-2a = 3-a=> 2a- a= 4 - 3=> a = 1=> d = 3 - a        = 3 - 1        = 2
```
one year ago
```							We know that sum of n terms of an AP is(n/2)[2a + (n – 1)d] , where a is the first term & d is the common difference of the AP.It is given that sum of an AP is n2 .So n2  = (n/2)[2a + (n – 1)d] i.e. n = a + (n – 1)d / 2Put n = 1  ,  1 = aPut n = 2  ,  2 = a + d / 2   i.e.  2 = 1 + d/2 d = 2 The common difference of the given AP is 2.
```
one year ago
Think You Can Provide A Better Answer ?

## Other Related Questions on Algebra

View all Questions »  ### Course Features

• 731 Video Lectures
• Revision Notes
• Previous Year Papers
• Mind Map
• Study Planner
• NCERT Solutions
• Discussion Forum
• Test paper with Video Solution  ### Course Features

• 101 Video Lectures
• Revision Notes
• Test paper with Video Solution
• Mind Map
• Study Planner
• NCERT Solutions
• Discussion Forum
• Previous Year Exam Questions